Subtract 54/12 from 5/81, Solve 5/81

Subtract 54/12 from 5/81

1^st number: 5/81, 2^nd number: 4 6/12

5/81 - 54/12 is -719/162.

Find the least common denominator or LCM of the two denominators:
LCM of 81 and 12 is 324

Next, find the equivalent fraction of both fractional numbers with denominator 324
For the 1st fraction, since 81 × 4 = 324,
5/81 = 5 × 4/81 × 4 = 20/324
Likewise, for the 2nd fraction, since 12 × 27 = 324,
54/12 = 54 × 27/12 × 27 = 1458/324
Subtract the two like fractions:
20/324 - 1458/324 = 20 - 1458/324 = -1438/324
After reducing the fraction, the answer is -719/162

MathStep (Works offline)

Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad